The Bravest are asking New Yorkers to give blood for a firefighter badly burnt during a raging Brooklyn house inferno last week.

Fire Rescue 2’s Robert Weidmann is undergoing surgery and skin grafts for second and third-degree burns over more than half of his body at Cornell Hospital, where he is in serious but stable condition.

His fire company is asking well-wishers to donate O negative blood donations for the father of two, or to donate other types of blood in his name so he can receive a credit.

Donors can give directly to Weidmann through the New York Blood Center by listing patient ID number 203859 and file 71614.